When a user is reading a file on an electronic device (such as computer, Personal Digital Assistant (PDA), mobile phone, e-paper, etc.), he/she may encounter some characters/words which he/she does not recognize or some characters/words whose pronunciations or meanings he/she cannot determine, such as characters/words which are rarely used or have more than one pronunciation. Such characters/words will hinder the user from fully understanding the content of the file.
In order to facilitate full understanding of the content of the file, in the prior art, if the user encounters a rare character/word when reading the file, he/she needs to stop reading to look up the character/word in a dictionary, for example, so as to determine the pronunciation and meaning of the character/word. Apparently, such lookup operation requires the user to interrupt his/her continuous reading process. This loss of reading continuity will severely degrade the reading experience of the user.